1. Field of the Invention
The present invention relates to a medicinal agent or food which potentiates the immune system of an animal, including a human being, to thereby protect the animal from infection, and a feed or feedstuff having an immunopotentiating activity.
The present invention also relates to a medicinal agent or food for regulating a function of the digestive tract or gastrointestine of an animal, including a human being, and a feed or feedstuff having the activity of regulating the function of the digestive tract or gastrointestine of an animal.
Further, the present invention relates to a medicinal agent for improving antibiotic absorption by an animal, including a human being, and a feed or feedstuff for improving antibiotic absorption by an animal.
Furthermore, the present invention relates to a medicinal agent for accelerating animal growth or for improving an egg production rate, egg weight, egg quality or eggshell strength of an animal and a feed or feedstuff having the activity of accelerating an animal growth or the activity of improving an egg production rate, egg weight, egg quality or eggshell strength of an animal.
2. Description of the Related Art
With the recent progress in immunology, it has come to be thought that the various maladies and infectious diseases of an animal, including a human being, are caused by a weakening or deficiency in the immune system of the animal.
For example, a human being frequently suffers from a weakening or deficiency in his immune system because of bronchial asthma, allergic diseases, articular rheumatism, autoimmune diseases, nutritional disorders, surgical operation, aging, cancer, organ transplantation, pregnancy or the like, resulting in the complication of a disease such as respiratory infections, sepsis or urinary infections.
Up to this time, various antibiotics have been administered to patients with such maladies or infectious diseases. Meanwhile, large-scale or overcrowded raising has been employed in the fields of animal husbandry and aquaculture in order to raise livestock, poultry or fish efficiently, and in such raising, it has been also a practice to administer a high dose of an antibiotic.
The repeated administration of an antibiotic for a long period causes the generation of antibiotic resistant bacteria to lower the effect of the antibiotic. Further, hospital infection has also become a significant problem. Under these circumstances, it has been expected to develop a preventive and therapeutic agent which can potentiate the immune system while reducing the dosage of an antibiotic.
Further, the overcrowded raising employed in the fields of animal husbandry and aquaculture has a problem in that various infectious diseases frequently break out because of stress or juvenile immunodeficiency. Furthermore, when a high dose of an antibiotic is administered as a countermeasure against the problem, there occur other problems that the antibiotic is not completely consumed and antibiotic resistant bacteria propagate in the environment.
Recently, animals, including human beings, have frequently suffered from various gastrointestinal diseases which are caused by a lowering or deficiency in the immune system, stress, dyspepsia or the like, and most of which are accompanied with diarrhea.
For example, a human being becomes susceptible to an infectious disease of the digestive tract as his resistance lowers, and representative examples of the infectious disease include bacterial, viral and parasitic diarrheas. Further, the above gastrointestinal diseases also include acute diarrheas caused by food poisoning and food allergy and chronic diarrheas caused by a disorder of digestion and absorption, excess gut hormone and colic diseases.
It has been the practice to administer an intestinal depressomotor for the intestines, an astringent, an irritant-absorbing agent, a torpent for enteric mucous membranes or various antibiotics against these gastrointestinal diseases.
Meanwhile, large-scale or overcrowded raising has been employed in the fields of animal husbandry and aquaculture to raise livestock, poultry or fish efficiently. In such raising, it has been a practice to administer the above therapeutic agents for the treatment of diarrhea caused by stress or dyspepsia. Particularly, a large amount of an antibiotic has been used for the prevention of infectious diseases.
The administration of the above depressomotor or astringent is essentially a nosotropic means, while that of an antibiotic is an etiotropic one. However, the repeated administration of an antibiotic for the prevention of infectious diseases has a problem that the preventive effect is lowered owing to the generation of antibiotic-resistant bacteria.
Under these circumstances, it has been expected to develop a novel preventive and therapeutic agent which can regulate gastrointestinal functions themselves and is safe.
Up to this time, various antibiotics have been administered to patients with various maladies or infectious diseases. Meanwhile, large-scale or overcrowded raising has been employed in the fields of animal husbandry and aquaculture to raise livestock, poultry or fish efficiently. In such raising, it has been a practice to administer a high dose of an antibiotic.
With respect to the use of an antibiotic, however, there have been pointed out problems such that the antibiotic accumulates in the body of an animal to affect the body and that the administration of a more potent antibiotic becomes necessary because of the generation of antibiotic-resistant bacteria. Further, the administration of an antibiotic to an animal is problematic also in that the environment is polluted with the antibiotic contained in the excrement of the animal. Under these circumstances, it has been expected that the dose of the antibiotic to be administered is reduced. In order to reduce the dose of the antibiotic, it has been believed effective that the absorption of the antibiotic through the digestive tract should be enhanced to attain an effect equal or superior to that attained by the administration thereof in a high dose, even when the antibiotic is administered in a low dose. However, no substance which can improve the absorption of an antibiotic has been found as yet.
In preparing animal feed, various attempts have been widely made at improving the feeding efficiency for animals and also at accelerating the growth thereof by adding various antibiotics to the feed, incorporating an increased amount of proteins into the feed, changing the feeding method or improving the dosage form of the feed.
With respect to the use of an antibiotic, however, there have been pointed out problems such that the antibiotic remains or accumulates in the body of an animal to affect the body and that the administration of a more potent antibiotic becomes necessary because of the generation of resistant bacteria. Further, the administration of an antibiotic to an animal is problematic also in that the environment is polluted with the antibiotic contained in the excrement of the animal. In addition, the effects obtained by varying the feeding method and the dosage form of the feed are limited. Under these circumstances, it is necessary to develop a safe and less problematic animal growth accelerator, feed and improver for the egg production rate, egg weight, egg quality or eggshell strength of animals.